diff --git a/ci/before_install.sh b/ci/before_install.sh
index 7279152fb0..8b0603eb16 100755
--- a/ci/before_install.sh
+++ b/ci/before_install.sh
@@ -32,6 +32,10 @@ if [[ "${TRAVIS_OS_NAME}" == osx ]]; then
   echo "Upgrade Python 3 pip."
   pip3 -q install --user --upgrade pip
 else
-  echo "Upgrade Python 3 pip."
-  pip3 -q install --user --upgrade pip
+  if command -v pip3 ; then
+    echo "Upgrade Python 3 pip."
+    pip3 -q install --user --upgrade pip
+  else
+    echo 'warning: missing pip3'
+  fi
 fi